Flotation process



Patented June 16, 1942" FLOTATIONTROCESS lfhilip A. Ray, Wilmington, Del., assignor to Hercules Powder Company, Wilmington, DeL,

a corporation of Delaware No Drawing. Application November 16, 1939, Serial N0. 304,707

9 Claims. 01. 200-166) This invention relates .to froth flotation processes and more particularly to froth flotation processes for separating metallic minerals wherein a blended pine oil or pine oil derivative is utilized as a frothing agent.

In the separation of metals from metal-bearing minerals or ores by froth flotation processes,

the percentage of recoveryof the metals is,

; largely due to the character of the frothing reagents employed. Nowadays it is desirable to get a very high recovery of metals in a very rapid and most efiicient manner. For example, today a recovery under 80%, in most cases is' 'considered poor, while years ago, a recovery of 60% was considered good. With the increase in efficiency of flotation processes, competition has become extremely keen and the successful operation of ore dressing or metallurgical plants may depend upon an increase in the recovery of metal of only a few percent. This is particularly soif the mineral or ore to (be dressed is of the low metal bearing quality or the plant operates on a small margin of profit.

Heretofore fatty acids, soaps, sulfonated. products, pine oil, cresylic acid, and special aliphatic alcohols have been utilized as frothing reagents.

, The first three mentioned frequently were quite unsatisfactory because the desired selectivity could not be obtained and more particularly because the gangue would float in large concentrations. An excessive amount'of reagents was often required to get a good recovery. This presented a serious economical problem, particularly when pine oil was used as a frother. Pine oil at times was not readily available on the market because the demand was greater than the supply and the prices thereof increased to an extent which made its use prohibitive.

An object of the present invention is to overcome the foregoing difficulties.

Another object is to improve froth flotation processes andincrease the recovery of metals or minerals. v

Another objectis to decrease the cost of froth flotation processes by utilizing frothing reagents appended claims, and various advantages not referred toherein will occur to one skilled in which are inexpensive, are readily available on the market at all times, and need not be-used in large quantities.

A further object is to utilize frothingagents under conditions to produce a maximum concentration and a more efficient separation of the minerals and metals. 7

Other and further objects will be obvious upon an understanding of the illustrative embodiment the art .upon employment of the invention in practice.

These objects are accomplished by frothing an .aqueous suspension of minerals .or ores in the presence of a blended pine oil or pine oil derivative'acting as a frother and containing an emulsifying agent and a hydrocarbon. In addition, if desired, the blend may be cut with suitable hydrocarbons and may beused in conjunction with suitable flotation agents. Preferably, the blend comprises equal volumes of pine oil or the like and hydrocarbons mixed with about 10% of an emulsifying agent, although good results may be attained with other proportions of materials as will be pointed out hereafter.

In accordance with the invention, I have found that pine oil or the like, suitably blended, can

be used advantageously as a froth flotation agent. When pine oil is referred to herein and in the appended claims, I mean pine oil of the commercial grade, synthetic pine oil, and pine oilde'rivatives prepared by air oxidation of terpene hydrocarbons and containing alcohols,

ethers, oxides, etc., such as terpinyl methyl ether or air oxidized acyclic terpene hydrocarbons.

I prefer to blend the pine oil and hydrocarbons with an emulsifying agent which may be sulfonated pinene-cresol condensate, sulfonated,

pinene-phenol condensate, s'ulfated dehydroabietyl alcohol, sulfonated higher fatty acid esters, such as sulfonated castor oil, or a compound (sold under the trade name of Hercota) which is made by heating ethanolamine or triethanolamine and vegetable oils, such as castor oil.

In the pine oil-emulsifying agent-hydrocarbon blendjI may use aliphatic or aromatic hydrocarbons, or mixtures thereof 1 have found that v hydrocarbons having a boiling range between C. and 300 C., but preferably between 150 toluol'). The boiling ranges of these hydrocan;

bons are as follows:' Troluoil to C.

Solvesso No. 2 '134' to C. Solvesso No. 3 185 to 215 C. Solvesso No. 4 215 to 282 C.

about to be described, 01' will be indicated in the 55 Kero ene 183 to 255 C,

. sponding to about 2500 g. of ore, was transferred trate' was taken'off. for 20 inutes.

The froth flotation reagents, that is, the pine .oil blends, may comprise pine oil and from 1 to 25%, but preferably from to emulsifier, and hydrocarbons in any desired proportions, 'although mixturesof equalvolumes' of pine oil and hydrocarbon are-fpreferred. The reagents, preferablyf are prepared them-'i prior .to add-= I {ing them to ;the' flotation tank tdjassure thorough admixture)- or the ingredien to i facilitate controlling.- ltheconcentration ereofin the course or flotation procesaybut may be added individually to the tank, if so desired. In practice, where minerals: or ores, particularly of. the metallic type are froth floated,-small amounts of I salts such as sodium cyanide or a thiophosphoric acid containing 6% thiocarbanilide (Aerofloat N0. 31) or other materials as indicated hereafter, may be utilized to assist in increasing the eifectiveness or the frothing. reagents.

In carrying out the froth flotation process, the ore or mineralLto be dressed, concentrated, or classified is first ground to a pulverized or finely divided state and is fed to a flotation tank of any well-known design which contains water. The

minerals andwater are mechanically agitated 5 and airor other suitablegas is bubbled therethrough. A desiredfaniount of flotation reagents ls added and these reagents are active to separate the desired, materialsifrom the undesired Example I A volume of a-lead ore flotation pulp, correto a 2000 g. flotation cell. Then 0.008flb. of sodiumcyanide per ton of ore, 0.06lb. of Aerofloat No. '31 (a thiophosphoric acid +-6% thiocarbanilide) and the frother as listed below, were added. Air waspassed' through the pulp and a concen- Pounds 1 y Frother l 1 g on Percent Pb in con} centrate Percent Pb recovery 0% of equal vol. of pine oil and erosene+l0? Hercota 90% of same lend+10% sul- -Ionated castor oil 90% of same blcnd+l0% sulfonated inene-phenol con,- densate, asalt Example II I The same procedure as in ExampleI was followed.

, v Sodium cyanide lb...per ton of ore 0.008' Aerofioat No. 31 do 0.047 Flotation time es .20

Pounds per ton Percent Pb in cencentrate Percent Pb Frother I recovery Example III The same procedure as in Example I was followed, exdept neither collector (Aerofloat No. 31)

nor sodium cyanide was added. The frother was the only reagent present. Flotation time 20 minutes;-

. Pounds Percent Pb v Percent Pb Frother r in con- 811 centrate recovery 90% of equal vol. of pine oil and kerosene-+10% Hercota 0. l5 43. 7 88. 4 Same as above 0. l7 49. 8 k 01. 1 90% of equal vol. of pine oil and a kerosene+l0% sulfonated casa to! oil 0. 15 49. 8 87. Same as above 0. 17 47. l 88.

Example IV One thousand ten (1010) gfof St. .loseph Lead Company's Bonne Terre, Missouri, minus8 mesh ,lead ore were ground-in a ball mill for 12 minutes with 1000 cc. of distilled water. The ground ore'was screened through a 65 mesh screen'and .pulp were added the following fiothers, but no other reagents. The tests were carried out for 20 minutes.

v P d P t Pb can a ercen Percent Pb Frother per in concenton mm f P 90% of equal volume of pine' 'oil and kerosene+l0% Herwta. 0. 20 68. 88 80. 3 00% of above blend-{40% sulionated water oil 0. 20 68. 70 76. 6- 90% pine oll+l0% suliouated castor oil .L 0. 20 43. 73 76. 3

Example V Pounds Percent Pb' Percent Pb Frother in 313$]: v recovery I 90% of equal volume of pine oil +kerosene+l0% sull'onated pinene-phenol condensate, Na salt -3. 0. 20 65. 89 88. 4 90% of above blend-+10% sulfonated pinene-cresol condensate Na salt 0. 20 64. 25 86. 2 90% of e ual volumes of terpinyl I methy ether+kerosene+l0% s onated pinene-phenolconde te, Na salt 0. 20 64.91 :7. of above blend+l0% sulfeted dehydroabietylalcoliol, I 90; sfallggnifinii i yufiun 0.20 60.41 93.4

o a ve en erc ta 0.20 65.41 04.8

In the above, it will be noted that tests were made with blends containing a terpene ether (from terpineol and methyl alcohol) in place of pine oil. These ga e satisfactory results.

Example VI low, were added. Air was passed through the pulp and a concentrate was taken on for 20 Example VII About 830 g. of minus 8 mesh Matahambrecopper ore from Santa Lucia, Cuba, were ground in a ball mill for 14 minutes with 1000 cc.- of distilled water. The ground ore, was screened through a 48-mesh screen and then transferred to a 1000 g. flotation cell and further diluted to about 16% solids. 111 addition to the frother, the following materials were added to the pulp: Sodium cyanide lb. per ton of ore 0.10 Lime a [on 1.20 Potassium ethyl xanthate do 0.18

Air was passed throughthe pulp and a concentrate was taken off for 10 minutes.

Pounds Percent Cu Percent Cu Frother per in con- 1 ton centrate retovery 90% of equal vol. of pine oil and kerosene-{40% sulfonated castor oil 0. 58 18.87 90.3 90% of same blend+l% Hercota 0.58 l 19.77 91.0

Example VIII ores, of the metal bearing type. The pine oil blends utilized in carrying .out the process provide a relatively high recovery. Relatively small amounts of the blends are effective to separate the metals from the gangue in an expedient manner, thereby decreasing the cost of the frothing reagents and increasing the plant capacity.

It will be understood that the details and examples hereinbefore set forth are illustrative only and that theinvention-a's broadly described and claimed is in no way limited thereby,

What I claim and desire to protect by Letters Patent is:

pension of said ores in the presence of .a frothl. A process for the froth flotation of sulfide ores which comprises frothing an aqueous susing agent comprising major proportions of pine About 1030 g. of the same Matahambre copper ore were ground in a ballmill for 14 minutes with 1000 cc. of distilled water. The ground ore was screened througha 48-mesh screenand then transferred to a 1000 g. flotation cell and further diluted to about20% solids. In addition to the fr'other, the following-materials were added:

Sodium cyanide "lb. perton of ore 0.08 Li e" do 1.00 Potassium. ethyl xanthate do 0.15

Air was passed'through the pulp and a concentrate was taken off for 10 minutes.

dounds Percent Cu Percent Cu Frothcr per in concenton I trate F of equal vol. of pine oil and kerosene+10% sulfonated cas- 1 toroil 0.48 18:52 89.5 Same as above .5 1.' 0. 25 20. 62 89. 0 of equal vol. oipine oil and kerosene+5% sulfonated cas- 1 toroil 0.25 22.86 85.5;

o of equal vol. of pine oil and lvesso No. 2+10% sulfonated castlor %il E .ii .&. 0. 25- 20.86 84. 8 90%olequ 'vo.o place an Solvesso No. 3+10% sullonoted eastor oil. -.i .a- 0.24 21. 97 85.! 90% of equal vol. of pine oi an Solvesso No. 4+l0% sulfo noted castor oil I 0. 48 17. 23 91. 5

The last four frothers were stage fed, at

start, and /2 after 5 minutes of the test.

From the foregoing description and examples,

it will be seen that the present invention provides an improved froth flotation process for separating, collecting, or classifying minerals or oil and a hydrocarbon compound and .a minor proportion of an emulsifying agent selected from the group consisting of sulfonated pinene-cresol condensate, sulfonated pinene-phenol condensate, sulfated dehydroabietyl alcohol, sulfonated higher fatty acid esters, ethanolamine-castor oil- -condensates and triethanolamine-castor oil condensates. 2. A processfor the froth flotation of sulfide ores which comprises frothing an aqueous suspension of' said ores in the presence of a frothing agent comprising major proportions of pine oil and a hydrocarbon compound and a minor proportion of an ethanolamine-castor oil condensate.

ores which comprises frothing an aqueous suspension of .said ores in the presence of a frothing agent comprising major proportions of pineoil and a hydrocarbon compound and a minor proportion of a triethanolamine-castor oil condensate.

4. A process for the froth flotation of sulfide ores which comprises frothing an aqueous suspension of said ores in the presence of a frothing agent comprising major proportions of pine oil 7 and a hydrocarbon-compound having a boiling range between about 100 C. and about 300 C. and a minor proportion of an emulsifyingagent selected from the group consisting of sulfonated pinene-cresol condensate, sulfonated pinenephenol condensate, sulfated dehydroabietyl alcohol, sulfonated higher fatty acid esters,

ethanolamine-castor oil condensates and triethanolamine-castor oil condensates.

5. A- process for the froth flotation of sulfide ores which comprises frothing an aqueous suspension of said ores in. the presence of 'a frothing agent comprising major proportions of pine oil and a hydrocarbon compound and from about 1 to about 25% of an emulsifying agent selected from the group consisting ofsulfonated pinenecresol condensate, sulfonated pinene phenol condensate. sulfated dehydroabietyl alcohol, sulfonated higher fatty acid .esters, ethanolaminecastor oil condensates and triethanolaminecastor oil condensates.

6. A processfor the froth flotationof sulfide.-

dehydroabietyl alcohol, sulfonated higher fatty acid esters, ethanolamine castor oil condensates and triethanolamine-castor oil condensates.-

3. A process for the froth flotation of sulfide.

7. A process for the froth flotation of sulfide ores whichcomprises frothing an aqueous suspension of said ores in-the presence of a frothing agent comprising major proportions of terpinyl methyl ether and kerosene and a. minor. 5 .proportion of. an ethanolamine-castor oil.condensate. r

8. A proeess for the froth flotation of sulfide ores which comprises frothing an aqueous suspension of said oresin the presence of a irothi'ng m agent comprising substantially equal volumes of a commercial pine oil-and kerosene and about 10% of an ethanolamine-castor oil condensate.

9. In a process for the froth flotation of sulfide ores which comprises frothing an aqueous suspension of, said ores in the presence of .a frothin'g agent comprising major proportions of pine oil and kerosene and a minorproportion of sulfonated castor oil.

- PHILIP A. RAY.,

g lt 3m? lid; 2, 236571;;

CERTIFICATE OF comcmox v mm 1 6, 191:.2. PHILIP: A; my.

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